Regulation of electrical systems.



G. CROSBY.

REGULATION OF ELECTRICAL SYSTEMS.

APPLICATION FILED JUNE Z-Z. I913.

Patented Jan. 14, 1919.

2 SHEETS--SHEET I- nvmv rm? 7 ATTOPA/ r8 G. CROSBY, REGUL'ATION OFELECTRiCAL SYSTEMS.

APPLICATION FILED JUNE 24. I915.

Patented Jan. H, 1.919.

2 SHEETS-SHEETZ.

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i J IW- ATTORNEYS UNITED sfra'rns arana? orrrorz.

GORHAM CROSBY, 0F GLEN RIDGE, NEW JERSEY, .AEtSIGNOR Ti) GOULD COURLERCOMPANY, 'A CORPORATION OF NEV? YORK.

REGULATION ELECTRLCAL SYSTEMS.

Specification of Letters Patent.

PatentedJan. 14, 1919.

Application filed June 24, 1915. Serial No. 36,031.

To all whom it may concern Be it known that I, Gonnaii Cnosnr, a citizenof the United States, and a resident of (llen Ridge, county of Essex,State of New Jersey, have invented certain new and useful Improvementsin the Regulation of Electrical Systems, of which the following is aspecification. I

My invention relates to the regulation of electrical systems, moreparticularly by the inclusion in the circ1.it to be regulated of twovariable resistances controlled in a manner to produce more eliicientregulation.

In many systems in which the work circuit is supplied from a. sourceofvariable voltage. such as in car lighting systems, wherein a generatorand storage battery are employed in operative relation to a work circuitor work circuits. it has been common to employ a compressible variableresistance in series between the battery and work cir cuit in regulatingthe voltage applied to the latter. If the load on the work circuit orcircuits is very heavy, it is found that either the compressiblevariable resistance or carbon pile must be so large as to be unwieldyand impractical or else the load will eX haust the capacity of thevariable resistance.

According to my invention I overcome these dilliculties by including inseries with the carbon pile v variable resistance, a second ariableresistance which may be of carbon pile type and which I preferablyoperate to increase the resistance thereof, When the voltage ofthc'soureo is materially higher than that across the work circuit.

Further objects, features and advantages will more clearly appear fromthe detailed description given below, taken in connection with theaccompanying drawings, which form a part of this specification.

In the drawings, Figure 1 is a diagram of a train lighting system,embodying my invention in one form. Fig. 2 is a similardiagram,illustrating a modification. Fig. 3 is a diagram of part of a similarsystem, illustrating a further modification. Fig. 4 is a diagram of asimilar system illustrating another modification.

Referring to Fig. 1, represents the main generator, which may be drivenat variable speed, as from a car axle of a train. The generator 1supplies the mains 2, 3 and 4. The main 4 branches oil from the main 3.5 represents a shunt field of the generator 1,

having in series therewith a carbon pile variable-resistance 6,;thepressure upon one end of which is varied by a lever 7 operated by asolenoid 9, whose windings are connected across the terminals of thegenerator, to be responsive to voltage variations thereof. The pressureupon the other end of the pile is controlled by a lever a solenoid 11,connected in series with the generator, so as to be responsive tocurrent variations in its total output. 12, 12, represent storagebatteries, which may be located in separate cars of the train, connectedacross the mains or train line conductors 2 and 3. which may also beplaced in separate cars of the train and connected across the mains ortrain line conductors 2 and 4.

When the generator is running at suflicient speed to supply the workcircuits, its voltage is regulated to maintain a constant output bymeans ofsolenoidll acting upon the pile (3, varying the strength of thecoil in a well known manner. \Vhen the bat teries have becomesubstantiallycharged,

which is indicated by a rise in voltage, with a consequent rise ingenerator voltage, the.

coil 9 becomes sulliciently energized. to relieve the pressure on theother end of the pile 6 through the lever 7. so that thereafter thegenerator voltage is maintained substantially constant, causingadecrease in the generator output and the stopping of the mains 2 and lof the work circuit and hav-' ing in series therewith carbon pile l8,operated by a lever 19, controlled by a solenoid 20, connected in shuntacross the work circuits. 21 represents a small carbon pile, thepressure upon which is varied by lever 22, by engagement therewith of aprojection 23 carried upon lever 16, so that when the coil 17 isweakened to a certain extent,

10, operated by allowing its core to drop, the member 23 on I lever 16engages the lever 22 and causes it to compress the pile 21. The pile 2113 then.

connected in. shunt across the pile 14, the circuit being throughconductor 24, member 23, lever 22, pile 21 and conductor 25. Thus, whenthe pile 14: is compressed substantially to its maximum, the pile 21 isthrown in shunt therowitlr by engagement of member 23 with lever '22,and upon further depression of the pile 21, the resistance that isregularly maintained between. the batteries and the lamps is practicallywill. The carbon pile 15 is similarly operated upon by a lever 26,controlled by a solenoid 27, connected across the work circuit andhaving in series therewith carbon pile 28. the pressure upon which iscontrolled by lever 29, which is operated by the solenoid 20 when a pin30, carried on a spindle 31, connected to the lower end of the core ofthe solenoid 20., engages the lever 29 to raise the same. A small carbonpile 32 operated upon by a lever 33, engaged by projection 34 on lever26, is arranged in shunt with pile 15, and operated in a mannor similarto that described with respect to pile 21. The pile 15 is normallymaintained under substantially maximum compression with pile 32compressed by the lever- 33.

'VVhen the voltage across the variable source tends to increase, thusincreasingthe strength of solenoid 20, it, through lever 19, compressespile 18, thereby increasing the strength of solenoid 17, relieving thepres sure on pile 14, so as to increase the resistance in series withthe work circuit and maintain the voltage across the Work circuit orwork circuits substantially constant. The tendency for the voltageacross the work circuits to decrease results in the weakening ofsolenoid 20, increasing resistance in pile 18, weakening of solenoid 17and decrease oi? resistance of pile 14, to maintain the voltage acrossthe work circuits substantially constant. As the batteries becomecharged, as above explained, and when the voltage across the generatorand batteries is materially higher than. that across the work circuits,the solenoid 20 will have raised its core sufficiently for the pin 30 toengage the.

lever 29. thereby decreasing the resistance of pile 28 inc1',easing thestrength of the solenoid 27, causing the lever 26 to relieve thepressure on pile 15, so that the resistance of the pile 15 will beincreased. This re: sults in the pile 15 taking a material portion ofthe voltage drop between the generator and batteries on one side and thework circuits on the other, so that pile 14 is not required to take theheavy current with a large voltage drop and in a greatly expandedcondition, which would likely be beyond its capacity. Part of the dropbeing carried by pile 15, the pile 14 is able to take care of the heavycurrent by reason of the fact that the drop thereacross is not large andit may be in a more or less compressed condition. lnorder that the pile14 need not be further afiected by variations in pile 18 after pile 15has begun to be affected by the variations caused in pile 28,- l haveshown pile 18 provided with a yielding abutment comprising the pivotedlever -15 which is drawn toward the pile by the tension of the springl6. When the lever 19 has been moved far enough to compress pile 18sufliciently to overcome the pressure of the spring 46 further movementof the lever has no substantial effect in decreasing the resistance ofpile 18 and therefore no substantial indirect eii'ect in increasing theresistance of carbon pile 1 1. After this point is reached furtherregulation can be effected practically alone by the compression of pile28 and its effect in increasing the resistance of pile 15. It will thusbe seen that the pile 14: operates throughout a certain range in voltagevariations of the source while the pile 15 operates throughout adifferent range of voltage variations. In the modification shown in Fig.2, similar" reference characters refer to similar parts, and the systemillustrated is substan-.

tially the same except that the coil 11 is shown connected in serieswith the batteries and not in series with the work circuits, so that itacts to regulate the generator for constant battery current. Also thepilot regulators 1S and have been omitted, the pile 1i being shown ascontrolled for voltage changes across the work circuit directly by thesolenoid 17, while the pile 15 is controlled by a solenoid having avoltage Winding 40 connected across compressible resistance 14, so as tobe responsive to voltage changes thereacross and a currentwinding 11connected in series with the variouswork circuits. lt will thus be seenthat the solen-oid comprising windings 40 and 41 act responsive tochanges in load (both voltage and current) carried by the carbon pile14, and the solenoid is attracted to increase the circuit resistance at15, only when the carbon pile 1% becomes overloaded. That is, the coils40 and 41 are wound to aid one an other, but do not have suflicientstrength to raise their core and relieve pressure on the )ll8 15 untilthe pile 1 1 hasbecoine overloaded.

The arrangement illustrated in Fig. 3 is the same as that of Fig. 2,except that coil 41 is omitted, so that resistance 1n pile 15 is.increased only when the voltage across the pile 14 increases to apredetermined point, indicating that the pile 1 1 would be overloaded bya further increase in voltage.

In Fig. 4 there is shown a similar arrangement, except that coil 40 isshown connccted across the generator and batteries and is designed tooperate the lever 26 to relieve pressure on the pile 15 in a similarmanner when'the voltage across the generator and batteries is materiallyhigher than that across the work circuits. Y

Thus, in each of the arrangements shown asecond variable resistance isprovided. in series with a compressible variable resist ance, and thesecond variable resistance is controlled to increase the resistance inseries with the first, when there is danger of the first becomingoverloaded, as indicated by a material increase in voltage ofthe sourceover that of the work circuit. It will be understood that if desired,suitable pilot or magnifying regulators, such as shown at 18, 20, inFig. 1, may be provided for the solenoids 17 and 40 in the otherfigures.

Although I have described my improvements in great detail and withrespect to car lighting-systems, I do not desire to be limited to suchdetails, as obviously, my improvements may be applied to many othersystems and to'many situations, and I in tend to cover all arrangementscoming within the language of the appended claims.

Having fully and clearly described my improvements, what I claim as newand de- 'sire tosecure by; Letters Patent is 1. In an electrical systemof distribution,

V the combination of a source of variable voltage, a work circuitsupplied thereby, a carbon p1le 1n series wlth the work circuit forregulating the voltage applied thereto, a

variable resistance in series with said pile, and means for increasingthe resistance of said variable resistance when the voltage ofthe sourceis relatively high, said means comprising a controlling coil responsiveto variations in voltage across sald carbon pile.

2. In an' electrical system of distribution,

a circuit to be regulated, a compressible variable resistance regulatingsaid circuit, a second variable resistance in series with thecompressible variable resistance, and means for increasing theresistance of said second variable resistance responsive to variationsinvoltage across said compressible variable resistance.

3. In an electrical system of distribution having a work circuitsupplied from a source of variable voltage, a variable resistance inseries with the work circuit controlled to maintain substantiallyconstant work circuit voltage,.a second variable resistance in series insaid Work circuit, and means for controlling it responsively to voltagedrop across the first resistance.

of said circuit and the other having its controlling means brought intoaction when the resistance value of the first has been in creased to apredetermined amount.

5. A circuit supplied from a source of variable voltage and to beregulated for constant voltage having a carbon pile in series therewith,jand means for increasing its resistance to a given value with increasesof voltage of said source to maintain substantially constant voltageapplied to said circuit, a second carbon pile in series with saidcircuit and means acting when said given value of the first pile hasbeen reached for increasing its resistance with further 1ncreases ofvoltage from said source.

6.. A circuit to be regulated from a source of variable voltage, twocarbon piles in series therewith, a voltage coil, means wherebysaid coilcontrols one of said piles until the same increases to a given value andwhereby said coil controls the second p1le when the voltage of thesource further increases without further acting on the first v ile. '7.In an electrical system of distribution havin a work circuit suppliedfroma source of variable voltage, a regulating mechanism controlling thework circuit voltage including a carbon pile resistance in series wlththe work circuit and means for varying the re- GORHAM CROSBY.

